Règle correspondante
Practice Relating to Rule 147. Reprisals against Protected Objects
Section A. Civilian objects in general
Switzerland’s ABC of International Humanitarian Law (2009) states:
Means and methods of warfare
Even in war not everything is allowed. Various means and methods are prohibited, including … Reprisals against the civilian population or against non-military objectives[.] 
Switzerland, Federal Department of Foreign Affairs, ABC of International Humanitarian Law, 2009, p. 29.